NM_014332.3:c.109G>T

Variant names:

• chrX-21743773-C-A
• rs387906707
• NM_014332.3:c.109G>T

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The NM_014332.3(SMPX):​c.109G>T​(p.Glu37*) variant causes a stop gained change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 23)
• Consequence: SMPX NM_014332.3 stop_gained
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 5.84
• Publications: 4 publications found

Genes affected

SMPX (HGNC:11122): (small muscle protein X-linked) This gene encodes a small protein that has no known functional domains. Mutations in this gene are a cause of X-linked deafness-4, and the encoded protein may play a role in the maintenance of inner ear cells subjected to mechanical stress. Alternatively spliced transcript variants have been observed for this gene. [provided by RefSeq, Dec 2011]

SMPX Gene-Disease associations (from GenCC):

• nonsyndromic genetic hearing loss

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• hearing loss, X-linked 4

  Inheritance: XL Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia
• myopathy, distal, 7, adult-onset, X-linked

  Inheritance: XL Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• X-linked nonsyndromic hearing loss

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-21743773-C-A is Pathogenic according to our data. Variant chrX-21743773-C-A is described in ClinVar as Pathogenic. ClinVar VariationId is 29946.Status of the report is no_assertion_criteria_provided, 0 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_014332.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMPX	NM_014332.3	MANE Select	c.109G>T	p.Glu37*	stop_gained	Exon 3 of 5	NP_055147.1
	SMPX	NR_045617.2		n.296G>T		non_coding_transcript_exon	Exon 3 of 6

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SMPX	ENST00000379494.4	TSL:1 MANE Select	c.109G>T	p.Glu37*	stop_gained	Exon 3 of 5	ENSP00000368808.3
	SMPX	ENST00000646008.1		c.109G>T	p.Glu37*	stop_gained	Exon 3 of 5	ENSP00000493671.1
	SMPX	ENST00000494525.1	TSL:5	n.109G>T		non_coding_transcript_exon	Exon 3 of 6	ENSP00000495170.1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 23

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Hearing loss, X-linked 4 Pathogenic:1

May 13, 2011

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.65
CADD	Pathogenic	36
DANN	Uncertain	1.0
FATHMM_MKL	Uncertain	0.92	D
PhyloP100		5.8
Vest4		0.28
GERP RS		6.0
Mutation Taster		=2/198	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
Splicevardb		2.0
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs387906707; hg19: chrX-21761891;